Evaluation of physicochemical characteristics of experimental resin infiltrant containing graphene oxide

This in vitro study aimed to evaluate the influence of 0.5% graphene oxide (GO) incorporated into an experimental resin infiltrant on its physicochemical and antibacterial properties compared to Commercial Icon (IC) and Experimental (E) groups.

Experimental groups were manipulated (TEGDMA and BisEMA based) with and without incorporation of 0.5% and commercial infiltrant were obtained. Fourier-transform infrared spectroscopy (FTIR) was used to assess the degree of conversion (DC) (n=5) (0.5ml) before and after photoactivation. Sorption (So) and solubility (Sol) (n=10) (5x1mm) were evaluated after 7 days of water storage. Three-point bending tests determined the elastic modulus (EM) and flexural strength (FS) (n=10) (7x2x1mm). Initial carious lesions were induced in bovine enamel (4x4mm) and treated according to the groups and analyzed through Confocal Laser Scanning Microscopy (CLSM) for penetration depth (n=3). Antibacterial activity was evaluated using a colony-forming unit (CFU) assay to assess biofilm inhibition, MTT metabolic test, and biofilm analysis via Scanning Electron Microscopy (SEM). Generalized linear models were applied for So, Sol, EM, and FS, while Kruskal-Wallis and Dunn's tests analyzed DC, CFU, and MTT.

GO differed from IC and E in DC after 80s photoactivation (82.9), exhibiting superior results. GO showed higher So and Sol values (13,96x10⁻⁵ and 6,39x10⁻⁵, respectively). IC demonstrated the best EM and FS (1.09 and 86.74, respectively). CLSM confirmed enamel infiltration for GO and IC. E showed the highest CFU (1.71 × 10⁷ CFU/ml), while GO had the lowest (2.22 × 10⁶ CFU/ml). E exhibited the highest MTT absorbance (0.2395 x 540nm).

Incorporating GO into the experimental infiltrant is feasible, but further studies are needed to optimize its properties.

Infiltrants with graphene oxide and commercial formulations both demonstrated satisfactory antibacterial and infiltration performance.